The Secret Languages of Ireland: with special reference to the origin and nature of the Shelta language, partly based upon collections and manuscripts of the late John Sampson . R.A. Stewart Macalister (1937) · Cambridge University Press (reissued by Craobh Rua Books, Armagh, 1997)

Ethnologue: Languages of the World . (2018) · edited by Simons, Gary F., Charles D. Fennig · http://www-ethnologue-com.eres.library.manoa.hawaii.edu.